3com S7906E Installationsanweisungen
1-101
Destinations : 6 Routes : 6
Destination/Mask Proto Pre Cost NextHop Interface
3.3.3.3/32 Direct 0 0 127.0.0.1 InLoop0
5.5.5.5/32 BGP 255 0 2.2.2.9 NULL0
20.1.1.0/24 OSPF 10 1563 100.1.1.1 Vlan12
100.1.1.0/24 Direct 0 0 100.1.1.2 Vlan12
100.1.1.2/32 Direct 0 0 127.0.0.1 InLoop0
120.1.1.0/24 BGP 255 0 2.2.2.9 NULL0
Issuing the display ip routing-table command on the CEs, you should see that the cost of the OSPF
route to the peer CE is now 10 (the cost configured for the sham link), and that the next hop is now the
VLAN interface 1 connected to the PE. This means that VPN traffic to the peer will be forwarded over
the backbone. Takes CE 1 as an example:
[CE1] display ip routing-table
Routing Tables: Public
Destinations : 9 Routes : 9
Destination/Mask Proto Pre Cost NextHop Interface
20.1.1.0/24 Direct 0 0 20.1.1.1 Vlan11
20.1.1.1/32 Direct 0 0 127.0.0.1 InLoop0
20.1.1.2/32 Direct 0 0 20.1.1.2 Vlan11
30.1.1.0/24 OSPF 10 1574 100.1.1.2 Vlan12
100.1.1.0/24 Direct 0 0 100.1.1.1 Vlan12
100.1.1.1/32 Direct 0 0 127.0.0.1 InLoop0
120.1.1.0/24 OSPF 10 12 100.1.1.2 Vlan12
127.0.0.0/8 Direct 0 0 127.0.0.1 InLoop0
127.0.0.1/32 Direct 0 0 127.0.0.1 InLoop0
Issuing the display ospf sham-link command on the PEs, you should see the established sham link.
Takes PE 1 as an example:
[PE1] display ospf sham-link
OSPF Process 100 with Router ID 100.1.1.2
Sham Link:
Area RouterId Source-IP Destination-IP State Cost
0.0.0.1 100.1.1.2 3.3.3.3 5.5.5.5 P-2-P 10
Issuing the display ospf sham-link area command, you should see that the status of the peer is Full:
[PE1] display ospf sham-link area 1
OSPF Process 100 with Router ID 100.1.1.2
Sham-Link: 3.3.3.3 --> 5.5.5.5
Neighbour State: Full
Area: 0.0.0.1
Cost: 10 State: P-2-P, Type: Sham
Timers: Hello 10 , Dead 40 , Retransmit 5 , Transmit Delay 1
Example for Configuring BGP AS Number Substitution
Network requirements
As shown in
, CE 1 and CE 2 belong to VPN 1 and are connected to PE 1 and PE 2
respectively. In addition, they use the same AS number 600.